SACRAMENTO — When Jim Cooper squared off against a fellow Democrat in last fall’s race to represent part of Sacramento and its southern suburbs in the state Assembly, it wasn’t clear at first who would win. Fewer than 1,000 votes separated them in the June primary.

But several weeks before Election Day, campaign committees — primarily funded by San Ramon-based Chevron and out-of-state oil companies — sealed Cooper’s victory by pouring more than $1 million into ads, consultants and polling that helped him beat his more liberal opponent by 11 points.

Cooper is one of a growing band of moderate Assembly Democrats who enjoyed generous support from big business as candidates and helped the oil and tobacco industries get their way in the final days of the legislative session that ended Sept. 11. The 20 or so moderates now make up about a quarter of the lower house.

Known around the Capitol as “the mods,” they forced Gov. Jerry Brown and Democratic legislative leaders to abandon a key provision of a bill that sought to combat global warming by dramatically reducing the state’s reliance on oil. The group also blocked efforts to regulate electronic cigarettes and increase the legal smoking age to 21.

It wasn’t until the end of the session that the true power of the Mod Squad came into focus — and by then it was too late for liberal Democrats to stave them off.

Experts say the growth of the moderate bloc is a testament to the success of electoral reform efforts — a new redistricting process, longer term limits and the “top-two” primary system chief among them — aimed at eroding the influence of extreme liberals and conservatives who have dominated the state’s political discourse for decades. However, it has also given an unexpected advantage to deep-pocketed corporations who have figured out that moderate Democrats can be their best allies in a state where Republicans are often an irrelevant minority.

“Sophisticated, well-funded special interests are playing a long game,” said Jessica Levinson, a campaign finance expert and Loyola Law School professor. “It makes a lot of sense to invest early in people who are attuned to your needs and are in position to vote your way when the time comes.”

Voters endorsed the new primary system in 2010 when they passed Proposition 14, billed as a way to force politicians to campaign toward voters in the middle rather than at the extremes. The top two finishers advance to the general election, even if they belong to the same party.

It was the brainchild of Abel Maldonado, then a moderate Republican state senator from Santa Maria. In 2009, he ransomed his state budget vote to force legislative Democrats to put the measure on the ballot.

A close look at how much money business interests have given moderate Democrats shows that campaign committees controlled by the California Chamber of Commerce or financed directly by Chevron, Philip Morris and other corporations invested $4.5 million in television ads, mailers, consultants and more to help 10 Democratic candidates win their 2012, 2013 and 2014 Assembly races. Those were the first elections since the top-two primary system and the independent commission’s less-partisan districts took effect.

“Part and parcel to shaping legislative outcomes is helping to elect people we believe will perform a certain way in Sacramento,” said Marty Wilson, a veteran GOP strategist hired by the California Chamber of Commerce in 2012 to revamp campaign strategy. “And because of changes to our term limits, many of these members are eligible to serve through the middle part of the next decade.”

The new term limits, which allow Assembly members to serve up to 12 years instead of six, were approved by California voters in 2012.

Wilson said the chamber supports Democrats over Republicans in districts where they know that a Democratic candidate has the best chance to win based on voter registration. And often, Democrats seeking to represent poor Central Valley areas welcome the money from business and industry because they have so few deep-pocketed constituents to call on for campaign contributions.

“Under the old system, these moderates never would have made it to the November ballot — and that’s driving progressives nuts,” said Allan Hoffenblum, editor of California Target Book, which handicaps legislative and congressional races.

To be sure, the business community isn’t the only deep-pocketed player in California elections. Labor unions spend as much or more getting liberal Democrats elected, said Jack Pitney, a political expert at Claremont McKenna College.

“Business needs Republicans like labor needs liberal Democrats,” he said. “But business is adapting to the reality of California politics and reaching beyond the Republican minority for new allies.”

Maldonado, a former lieutenant governor appointed by Gov. Arnold Schwarzenegger, conceded that the top-two primary may have enhanced special interests’ influence in some races. However, he thinks that overall the Legislature is made up of members who are more open-minded, reasonable and pragmatic than before the system took effect.

“At the end of the day, members must vote their districts, vote their consciences and vote with the people who put them in office in mind,” Maldonado said.

But President Pro Tem Kevin de León says bluntly that the top-two primary has been “a bust” that’s intensified the iron grip of money in politics. And unlike the Senate, which last year banned fundraising at the end of session after two senators were indicted on charges of taking bribes, Assembly members are free to seek campaign cash year-round. This year, they held more than 75 fundraisers after returning from summer recess.

“The idea that this so-called good-government reform would help special interests further game the system by doubling-down on candidates of their choice — I didn’t see it coming,” de León said. “No one saw it coming.”

After Cooper, the biggest beneficiaries of money from business and industry have been Assemblymen Mike Gipson, D-Carson; Tony Thurmond, D-Richmond; Rudy Salas; D-Bakersfield; and Tom Daly, D-Anaheim. Each saw at least $420,000 in independent expenditures to help their campaigns.

Assemblyman Adam Gray, a moderate Democrat from Merced, received nearly $400,000 from business and industry committees in 2012 and 2014.

In an interview a day before the ambitious 50 percent oil-reduction target was deleted from SB350 — de León’s climate-change bill — because it lacked the support of most moderate Democrats, Gray scoffed at any suggestion that his opposition to the target was linked to concerns about the oil industry’s profits.

“I’m trying to make sure the well-being of our poorest communities isn’t sacrificed for the sake of clean air,” he said. “I shouldn’t have to choose between good jobs and clean air for my constituents. We deserve both.”

Cooper, Gipson, Salas, Daly and Assemblyman Henry Perea, D-Fresno, a leader of moderate Democrats in the Assembly who was elected before the top-two primary system took effect, all declined repeated requests to speak about the group’s recent ascent to power.

One of the only legislators who was showered with oil industry money but supported the original bill was Thurmond, a progressive Democrat.

“One of my colleagues said on the floor that this bill would increase costs on the poor,” he said. “I don’t understand where that analysis came from. And even if there are increased costs, the benefits in terms of air quality and health far outweigh them.”

Similarly, Sen. Mark Leno, D-San Francisco, one of the upper house’s most liberal lawmakers, was caught off guard earlier this year when his bill seeking to regulate e-cigarettes as tobacco products stalled in an Assembly committee controlled by Democrats who had accepted more than $100,000 in campaign contributions from tobacco companies since 2013.

E-cigarettes mimic smoking by heating a nicotine-infused liquid to produce a vapor that users can inhale. Their use among middle- and high-school students tripled from 4.5 percent in 2013 to 13.4 percent in 2014, according to a report published earlier this year by the U.S. Centers for Disease Control and Prevention.

Leno was hoping for a different outcome when he reintroduced the bill in July as part of a special legislative session on health care funding. But in the end, those same moderate Assembly Democrats who scuttled the measure’s chances in committee blocked the lower house from taking up the bill as the Legislature wrapped up its business.

“To succeed, I need to summon more patience with my colleagues because merely venting my displeasure will not produce the results I’m fighting for,” Leno said. “The best antidote to moneyed special interests are the voices of everyday constituents, and I sincerely hope they make their voices heard in those members’ district offices this fall.”

Leno also may need some luck. Next year, 16 Assembly seats will open up as the old term limits force legislators to retire, meaning the Mod Squad could become even more of a Capitol force.

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